GUNS Magazine September 2013 Digital Edition - Page 24

aCCuRaTe handgun handloadS iF you’ll take the time, the results can be impressive. illions of words have been written about techniques for constructing accurate rifle ammunition, but relatively little appears about making accurate handgun ammo. This is partly due to so many handgunners simply settling for plinking or blasting accuracy. Instead of dinking around with time-consuming details, they just want to load ammo and go shoot. But partly it’s because traditional handgun cases come out of a sizing die in very straight condition, unlike bottlenecked rounds sized in common dies. Straight cases tend to result in straightly seated bullets, the most basic prerequisite for accurate ammunition. However, a few techniques can really improve the accuracy of handgun handloads. The first step is to use consistent brass, both in wall thickness and length. This means of course, using the same brand and lot of brass, instead of range pickups. While it’s theoretically possible to lathe-turn handgun brass, just like benchrest shooters turn the necks of rifle cases, it’s far easier to either buy consistent brass in the first place, or sort the cases with a micrometer, such as the neck-thickness setting on an RCBS Casemaster. I look for cases differing no more than 0.001 inch when measured anywhere around the mouth, because bullets fired from How much do accuracy handloading techniques help? It depends on where you start from, but they can definitely make a difference. It certainly worked with this S&W Model 57 .41 Magnum. M John barsness brass with consistent neck thickness start down the bore straighter. As an example, I recently compared some brand-new Starline .45 ACP brass with some brand-new .45 ACP’s from another well-known American manufacturer. The Starline cases all had less than 0.001-inch difference in wall thickness at the mouth, while 23 percent of the other brand’s cases varied more than 0.001inch, up to 0.003 inch. While you can cull cases of varying wall thickness, many handloaders prefer buying very uniform brass in the first place. All the cases should be trimmed to the same length. This is especially important when handloading for semi-autos, since most rimless rounds for autos headspace off the mouth of the case. You may find an auto shoots more accurately with cases trimmed to a certain length—and not necessarily the maximum SAAMI length. After trimming, the mouths shouldn’t be chamfered nearly as much as with rifle cases. Instead the tiny burr (if any) around the mouth should be barely knocked off, leaving a definite flat surface on front edge of the mouth. This creates more consistent crimping and, in autoloaders, more consistent headspacing. Some handgun handloaders also weight-sort brass, then use a tool to cut uniform primer pockets. However, neither has nearly as much effect on accuracy as neck thickness or length; I usually bypass weighing and uniforming, especially with top-quality cases. (That batch of Starline .45 ACP brass varied only 0.6 grain in weight… meaningless in the real world.) The next step is belling the mouth, and consistent neck thickness and trimming also help here. Ideally, belling should be kept at the minimum amount necessary to easily accept bullets. Deeper belling leaves less case wall to help seat the bullet straight, and also work-hardens the brass more, affecting both case life and crimping consistency. Primers definitely matter more in handgun loads than rifle loads, since handgun powders are much faster burning, and the space inside the case relatively tiny. The general rule is to use milder primers for small amounts of easily ignited flake powder, and hotter primers (usually but not always called magnums) for larger amounts of harder-to-ignite ball powders, but general rules don’t always apply. Some 24 W W W. G U N S M AG A Z I N E . C O M • S E P T E M B E R 2 0 1 3